Technical Field
The present disclosure relates generally to conveyances, and more particularly to a conveyance which slides on two skis or snowboards, and which may be used on snow or other slippery surface.
Background Art
Conveyances which ride on ski-like boards rather than wheels are well know. Typically, such conveyances are used both for transportation and recreation on snow. For example U.S. Pat. Nos. 4,244,436 and 4,286,682 illustrate motorized versions of such conveyances on which an individual rides.
Unpowered conveyances used both for transportation and recreation on snow and upon which an individual rides are also known. For example, United States Patent Application Publication no. US 2009/0230641 (“the '641 publication”) entitled “Snow Ski-Bike” discloses a conveyance that includes a seat upon which an individual rides. The disclosed snow ski-bike has a suspension system that includes front and rear ski pivot assemblies connected respectively at opposite ends of the ski-bike's main frame. The '641 publication depicts a ski attached to a lower surface of each ski pivot assembly that permits the attached ski to rotate about a horizontal axis passing therethrough. A horizontal leveler shock absorber connects between each ski pivot assembly and a forward end of the ski attached thereto. The '641 publication discloses that after the ski strikes an obstacle on terrain the horizontal leveler shock absorber, upon cycling though its rebound phase, returns the ski to the ski's true horizontal orientation. The '641 publication also depicts a hand operated brake attached to a rear end of each ski. The '641 publication's FIG. 3 depicts a rear pivoted double swingarm included in the frame that operatively connects between the rear ski pivot assembly and the ski-bike's main frame. The '641 publication also discloses a rear suspension shock absorber that connects between the ski-bike's main frame and the rear pivoted double swingarm.
U.S. Pat. No. 7,537,221 entitled “Snow-Sliding Vehicle” (“the '221 patent”) has an overall configuration similar to the “Snow Ski-Bike” disclosed in the '641 publication. The '221 patent's “Snow-Sliding Vehicle” slides on a rear bearing runner and a front directional runner respectively located at opposite ends of a stiff frame. A pivoting steering column, that includes a fork having axial dampeners, extends downward from one upper end of the stiff frame to the front directional runner. Rotatable joints interconnect the lower end of the forks included in the steering column to the directional runner so the runner is free to rotate about a horizontal axis. A dampening device disclosed in the '221 patent also interconnects the directional runner to lower end of the fork. A flat base, upon which an individual stands while riding the vehicle, that is located at the rear end of the stiff frame, includes a hinged rear portion. A dampening device also interconnects the hinged rear portion of the base with the '221 patent's stiff frame. A dual parallel knuckle joint, that extends downward beneath the base, interconnects between a forward end of the base and the front end of the bearing runner. A transverse joint, that depends beneath the hinged rear portion of the base, is also fastened to the bearing runner. This arrangement locates the bearing runner beneath the base substantially parallel to the front, un-hinged portion of the base. The '221 patent discloses a dampening device fastened at one end to the stiff frame, that extends downward therebelow and passes through the dual parallel knuckle joint, to be fastened at an opposite end thereof to the front end of the bearing runner. Separation of the base into two portions interconnected by the hinge in combination with the interconnecting pairs of joints and corresponding dampening devices allows a folding movement at the rear end of the vehicle so the bearing runner is free to adapt to a sliding surface's topography without burdening the vehicle's freedom of displacement by a user's weight.
U.S. Pat. No. 6,783,134 entitled “Ski Vehicle” (“the '134 patent”) has an overall configuration similar to that of the “Snow Ski-Bike” disclosed in the '641 publication and the vehicle disclosed in the '221 patent. The '134 patent's vehicle includes frame that can be collapsed into a substantially compressed configuration so the vehicle can be transported in a car or plane. A lower end of a moveable parallelagramic linkage included in the frame has a pair of pivot points at which the rear ski attaches to the frame. To provide a smoother ride, a shock absorber, mounted within the parallelagramic linkage, compresses and dampens the vehicle's motion when the rear ski encounters irregularities in topography. The parallelagramic linkage maintains the rear ski in an essentially fixed orientation with respect to the frame and restricts the rear ski from freely pivoting around the pivot points located where the rear ski attaches to the frame. Instead, rear ski moves substantially parallel to a lower portion of the frame to provide a smoother ride for the ski vehicle's rider. The frame disclosed in the '134 patent also includes a foot pedal that when depressed rotates a skid plate, located where the rear ski attaches to the parallelagramic linkage, downward through a hole that pierces a rear ski into snow beneath the rear ski.